Fibreglass reinforced plastic

ABSTRACT

Provided herein is a resin composition containing milled fibreglass and graphene. Also provided herein is a composite material containing cured resin composition, fibreglass reinforced resin containing the composite material and further fibreglass, a laminate including a layer of the fibreglass reinforced resin, and methods of making the resin composition, composite material and fibreglass reinforced resin. The composition, composite material and fibreglass reinforced resin and laminate find use in, for example, the construction of swimming pools and spa pools.

CROSS-REFERENCE TO RELATED APPLICATIONS

This disclosure claims priority to Australian Application No.2020903571, filed 2 Oct. 2020, to Canadian Application No. 3105263,filed 7 Jan. 2021 and U.S. Patent Application No. 63/09,0848, filed 13Oct. 2020, the contents each of which is incorporated herein byreference for all purposes.

FIELD

This disclosure generally relates to fibreglass reinforced plastic, inparticular to fibreglass reinforced plastic which contains dispersedgraphene. The fibreglass reinforced plastic finds use in the manufactureof fibreglass laminates suitable for the construction of swimming poolsand spa pools.

BACKGROUND

Fibreglass reinforced plastic (FRP) is a composite material made of apolymer matrix reinforced with fibres. FRP is commonly used in theaerospace, automotive, marine, and construction industries and findswidespread use in the manufacture of pre-formed swimming pools.

FRP swimming pools may be manufactured by spraying a mixture of choppedfibreglass and uncured polymer resins onto a mould to provide a layer offibreglass composite material. The layer of composite material may beaugmented with other layers so as to provide a laminate structure. Thelaminate structure may comprise several layers of FRP and layers ofnon-FRP materials, such as polyester gelcoats and a structural core.After curing, the structure is released from the mould.

Other methods of manufacturing a FRP swimming pool include wet layup,however the spray method is advantageous from an economic perspective.

Despite advances in FRP composites, developing consumer regulations andstatutory requirements governing the strength requirements forfibreglass swimming pools to withstand the soil loadings and conditionssuch as expansive clay, and hydrostatic and hydrodynamic pressure hascreated a need to increase the flexural strength and flexural modulus ofa fibreglass swimming pool to withstand these additional loads.

Graphene is known to increase the strength and durability of compositematerials however it is difficult to homogeneously disperse the graphenethroughout uncured polymer resin.

Often large visible particles and agglomerates of graphene may remainwhich may compromise strength or, in the case of application in swimmingpool manufacture, may promote osmotic blistering.

In view of the foregoing, it would be desirable to develop newfibreglass reinforced plastic composites that address one or more of theaforementioned needs or problems.

The reference in this specification to any prior publication (orinformation derived from it), or to any matter which is known, is not,and should not be taken as an acknowledgement or admission or any formof suggestion that the prior publication (or information derived fromit) or known matter forms part of the common general knowledge in thefield of endeavour to which this specification relates.

SUMMARY

The present disclosure is directed to resin compositions, compositematerials, fibreglass reinforced plastic, and laminates containing thefibreglass reinforced plastic. In particular, the present disclosure isdirected to composite materials containing cured polymer resin,grapheme, milling media and milled fibreglass. The graphene is presentin a dispersed state which advantageously provides high strength to thecomposites. Laminates containing fibreglass reinforced plastic accordingto the present disclosure also demonstrate reduced levels of moistureuptake compared with conventional laminates. Reduced levels of moistureuptake can be beneficial for properties such as lifetime of thelaminate.

In one aspect the present disclosure provides a resin composition, saidresin composition comprising:

-   -   a) one or more curable resins;    -   b) graphene;    -   c) one or more milling media; and    -   d) milled fibreglass.

In embodiments, the one or more milling media have a diameter betweenabout 30 micron and about 150 micron.

In embodiments, the one or more milling media are hydrophobic.

In embodiments, the one or more milling media are insoluble in the resincomposition.

In embodiments, the one or more milling media are inert.

In embodiments, the crushing strength of the one or more milling mediamay be greater than about 2000 psi (13.79 MPa), or greater than about3000 psi (20.70 MPa), or greater than about 4000 psi (27.58 MPa).

In some embodiments, the crushing strength of the one or more millingmedia may be between about 2000 psi (13.79 MPa) and about 4000 psi(27.58 MPa).

In embodiments, the one or more milling media may have a Mohs hardnessof greater than about 4, or greater than about 5, or greater than about6.

In embodiments, the one or more milling media may have a Mohs hardnessfrom about 4 to about 7, or from about 5 to about 7.

In embodiments, the one or more milling media comprise one or more ofsilicon oxides or aluminium oxides.

In embodiments, the one or more milling media comprise one or more ofhollow glass microspheres, cenospheres and expanded glass aggregate.

In embodiments, the resin composition comprises:

-   -   a) from about 50 wt. % to about 80 wt. % of one or more curable        resins;    -   b) from about 0.1 wt. % to about 2 wt. % graphene;    -   c) from about 0.75 wt. % to about 35 wt. % of one or more        milling media; and    -   d) from about 3 wt. % to about 20 wt. % of milled fibreglass;        based on the total weight of resin composition.

In embodiments, the one or more curable resins comprise one or morecurable polyester resins, vinyl ester resins and epoxy resins. The oneor more curable resins may comprise one or more of bisphenol A vinylester resin, terephthalate resin, terephthalate-NPG resin, isophthalateresin, isophthalate-NPG resin, orthophthalate resin, orthophthalate-NPGresin, and urethane acrylate modified resins.

In embodiments, the one or more curable resins comprise a vinyl esterresin and terephthalate-NPG resin.

In embodiments, the one or more curable resins comprise a urethaneacrylate modified resins.

In some embodiments, the amount of vinyl ester resin comprises greaterthan 10% by weight, based on the total weight of resin in the resincomposition, 20% by weight, or greater than 30% by weight, or greaterthan 40% by weight, or greater than 50% by weight, or greater than 60%by weight, or greater than 70% by weight, or greater than 80% by weight,or greater than 90% by weight, based on the total weight of resin in theresin composition.

In embodiments, the graphene has an average platelet size between about1 micron and about 100 micron, or between about 5 micron and about 50micron, or between about 10 micron and about 30 micron.

In embodiments, the hollow glass microspheres have a diameter betweenabout 30 micron and about 150 micron.

In embodiments, the hollow glass microspheres have a diameter betweenabout 20 micron and about 150 micron.

In embodiments, the crushing strength of the hollow glass microspheresmay be greater than 2000 psi (13.79 MPa), to enable processing andspraying without the collapse of the hollow glass microspheres.

In some embodiments, the crushing strength of the hollow glassmicrospheres may be between about 2000 psi (13.79 MPa) and about 3000psi (20.70 MPa).

In embodiments, the hollow glass microspheres may have a Mohs hardnessof greater than about 4, or greater than about 5, or greater than about6.

In embodiments, the hollow glass microspheres may have a Mohs hardnessfrom about 4 to about 7, or from about 5 to about 7.

In embodiments, the cenospheres have a diameter between about 30 micronand about 150 micron.

In embodiments, the crushing strength of the cenospheres may be greaterthan about 3000 psi (20.70 MPa).

In some embodiments, the crushing strength of the cenospheres may bebetween about 3000 psi (20.70 MPa) and about 4000 psi (27.58 MPa).

In embodiments, the cenospheres may have a Mohs hardness of greater thanabout 4, or greater than about 5, or greater than about 6.

In embodiments, the cenospheres may have a Mohs hardness from about 4 toabout 7, or from about 5 to about 7.

In some embodiments, the resin composition comprises both hollow glassmicrospheres and cenospheres.

In some embodiments, the milled fibreglass has a fibre length betweenabout 100 microns and about 1000 microns.

In embodiments, the milled fibreglass further comprises a sizing agent.

In some embodiments, the resin composition further comprises athixotropic agent, for example fumed silica, preferably hydrophobicfumed silica.

In some embodiments, the resin composition further comprises one or moreaccelerators, promoters, inhibitors, air release agents, wetting agentsand silanes.

In some embodiments, the resin composition comprises a silane which is3-methacryloxypropyltrimethoxysilane.

In some embodiments, the resin composition has a viscosity from about500 cP (0.5 Pas) to about 6000 cP (6 Pas).

In another aspect the present disclosure provides a composite material,said composite material comprising:

-   -   a) one or more cured resins;    -   b) graphene;    -   c) one or more milling media; and    -   d) milled fibreglass.

In embodiments, the one or more milling media have a diameter betweenabout 30 micron and about 150 micron.

In embodiments, the one or more milling media are hydrophobic.

In embodiments, the one or more milling media are insoluble in thecomposite material.

In embodiments, the one or more milling media are inert.

In embodiments, the crushing strength of the one or more milling mediamay be greater than about 2000 psi (13.79 MPa), or greater than about3000 psi (20.70 MPa), or greater than about 4000 psi (27.58 MPa).

In some embodiments, the crushing strength of the one or more millingmedia may be between about 2000 psi (13.79 MPa) and about 4000 psi(27.58 MPa).

In embodiments, the one or more milling media may have a Mohs hardnessof greater than about 4, or greater than about 5, or greater than about6.

In embodiments, the one or more milling media may have a Mohs hardnessfrom about 4 to about 7, or from about 5 to about 7.

In embodiments, the one or more milling media comprise one or more ofsilicon oxides or aluminium oxides.

In embodiments, the one or more milling media comprise one or more ofhollow glass microspheres, cenospheres and expanded glass aggregate.

In embodiments, the composite material comprises:

-   -   a) from about 50 wt. % to about 80 wt. % of one or more cured        resins;    -   b) from about 0.1 wt. % to about 2.0 wt. % graphene;    -   c) from about 0.75 wt. % to about 35 wt. % of one or more        milling media; and    -   d) from about 3.0 wt. % to about 20 wt. % of milled fibreglass;        based on the total weight of the composite material.

In embodiments, the one or more cured resins comprise one or more curedpolyester resins, cured vinyl ester resins and cured epoxy resins. Theone or more cured resins may comprise one or more of bisphenol A vinylester resin, terephthalate resin, terephthalate-NPG resin, isophthalateresin, isophthalate-NPG resin, orthophthalate resin, orthophthalate-NPGresin and urethane acrylate modified resins.

In embodiments, the one or more cured resins comprise a cured vinylester resin and cured terephthalate-NPG resin.

In embodiments, the one or more cured resins comprise a cured urethaneacrylate modified resin.

In some embodiments, the cured vinyl ester resin comprises greater than10% by weight based on the total weight of cured resin in the resincomposition, or greater than 20% by weight, or greater than 30% byweight, or greater than 40% by weight or greater than 50% by weight, orgreater than 60% by weight, or greater than 70% by weight, or greaterthan 80% by weight, or greater than 90% by weight, based on the totalweight of cured resin in the resin composition.

In embodiments, the graphene has an average platelet size between about1 micron and about 100 micron, or between about 5 micron and about 50micron, or between about 10 micron and about 30 micron.

In embodiments, the hollow glass microspheres have a diameter betweenabout 30 micron and about 150 micron.

In embodiments, the crushing strength of the hollow glass microspheresmay be greater than 2000 psi (13.79 MPa), to enable processing andspraying without the collapse of the hollow glass microspheres.

In some embodiments, the crushing strength of the hollow glassmicrospheres may be between about 2000 psi (13.79 MPa) and about 3000psi (20.70 MPa).

In embodiments, the glass microspheres may have a Mohs hardness ofgreater than about 4, or greater than about 5, or greater than about 6.

In embodiments, the glass microspheres may have a Mohs hardness fromabout 4 to about 7, or from about 5 to about 7.

In embodiments, the cenospheres have a diameter between about 20 micronand about 150 micron.

In embodiments, the cenospheres have a diameter between about 30 micronand about 150 micron.

In embodiments, the crushing strength of the cenospheres may be greaterthan about 3000 psi (20.70 MPa).

In some embodiments, crushing strength of the cenospheres may be betweenabout 3000 psi (20.70 MPa) and about 4000 psi (27.58 MPa).

In embodiments, the cenospheres may have a Mobs hardness of greater thanabout 4, or greater than about 5, or greater than about 6.

In embodiments, the cenospheres may have a Mohs hardness from about 4 toabout 7, or from about 5 to about 7.

In embodiments, the composite material comprises both hollow glassmicrospheres and cenospheres.

In embodiments, the milled fibreglass has a fibre length between about200 microns and about 1000 microns.

In embodiments, the milled fibreglass further comprises a sizing agent.

In embodiments, the composite material further comprises one or morethixotropic agents, for example fumed silica, preferably hydrophobicfumed silica.

In another aspect of the present disclosure there is provided afibreglass reinforced resin comprising the composite material accordingto any one or more of the herein disclosed embodiments and furtherfibreglass.

In embodiments, the further fibreglass has a fibre length greater thanabout 1 mm, or greater than about 5 mm, or greater than about 8 mm.

In embodiments, the further fibreglass has a fibre length from about 5mm to about 20 mm, or from about 8 mm to about 16 mm.

In embodiments, the fibreglass reinforced resin has a flexural strengthgreater than about 124 MPa, or greater than about 130 MPa, or greaterthan about 140 MPa, or greater than about 150 MPa, or greater than about160 MPa.

In embodiments, the fibreglass reinforced resin has a flexural strengthbetween about 124 MPa and about 160 MPa, or between about 140 MPa andabout 160 MPa.

In embodiments, the fibreglass reinforced resin has a flexural modulusgreater than about 6,750 MPa, or greater than about 7,000 MPa, orgreater than about 7,250 MPa, or greater than about 7,500 MPa, orgreater than about 7,700 MPa, or greater than about 8,000 MPa, orgreater than about 8,500 MPa, or greater than about 9,000 MPa, orgreater than about 9,500 MPa, or greater than about 10,000 MPa.

In embodiments, the fibreglass reinforced resin has a flexural modulusbetween about 7,700 MPa and about 10,000 MPa, or between about 8,500 MPaand about 10,000 MPa.

In embodiments, the fibreglass reinforced resin has a tensile strengthgreater than about 100 MPa, or greater than about 110 MPa, or greaterthan about 120 MPa, or greater than about 130 MPa, or greater than about140 MPa.

In embodiments, the fibreglass reinforced resin has a tensile strengthbetween about 100 MPa and about 140 MPa, or between about 110 MPa andabout 140 MPa.

In another aspect of the present disclosure there is provided a laminatecomprising one or more layers of fibreglass reinforced resin accordingto any one or more of the herein disclosed embodiments.

In embodiments, the laminate may further comprise one or more layers ofanother material, for example one or more layers of a polymer ormixtures of polymers.

In embodiments, the one or more other layers comprise one or moregelcoats. The nature of the gelcoat is not particularly limited andincludes materials typically utilized as gelcoats in the manufacture ofswimming pools and in the marine industry.

In embodiments, the gelcoat may comprise one or more layers.

Exemplary gelcoats comprise one or more polyesters and vinyl esters. Insome embodiments, the gelcoat is a polyester gelcoat. In someembodiments, the gelcoat is a vinyl ester gelcoat.

In another aspect of the present disclosure there is provided a swimmingpool or spa pool comprising a laminate according to any one or more ofthe herein disclosed embodiments.

In another aspect of the present disclosure there is provided a methodof preparing a resin composition according to any one or more of theherein disclosed embodiments, said method comprising:

-   -   a) forming a mixture of one or more curable resins, graphene,        and one or more milling media;    -   b) agitating the mixture to disperse the graphene; and    -   c) adding milled fibreglass.

The method may further comprise adding one or more thixotropic, airrelease, wetting agents and/or silanes.

The method may further comprise degassing the resin composition.

In another aspect of the present disclosure there is provided a methodof preparing a resin composition according to any one of the hereindisclosed embodiments, said method comprising the following steps:

-   -   a) forming a mixture of one or more curable resins, graphene,        and one or more milling media;    -   b) agitating the mixture to disperse the graphene;    -   c) combining the mixture formed in b) with one or more further        curable resins and one or more further milling media, and        agitating to further disperse the graphene; and    -   d) adding milled fibreglass.

The method may further comprise the step of adding one or morethixotropic, air release, wetting agents and/or silanes.

The method may further comprise the step of degassing the resincomposition.

In another aspect of the present disclosure there is provided a methodof preparing a composite material according to any one or more of theherein disclosed embodiments comprising curing a resin compositionaccording to any one or more of the herein disclosed embodiments.

In another aspect of the present disclosure there is provided a methodof manufacturing a fibreglass reinforced resin comprising the step ofspraying a mixture comprising a resin composition according to any oneor more of the herein disclosed embodiments and fibreglass rovings andcuring the resin.

The fibreglass reinforced plastic as disclosed herein may comprise oneor more of the following advantages in comparison to traditionalfibreglass reinforced plastics:

-   -   significantly higher flexural strength    -   significantly higher flexural modulus    -   significantly higher tensile strength.

The laminates as disclosed herein may comprise one or more of thefollowing advantages:

-   -   Low water vapour transmission through the laminate    -   Less likely to generate osmotic blistering    -   High water resistance    -   High chemical resistance.

These performance advantages make the herein disclosed fibreglassreinforced resins and laminates ideally suited in the manufacture ofswimming pools and/or spa pools.

Further features and advantages of the present disclosure will beunderstood by reference to the following drawings and detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow diagram of a method of making a resin compositionaccording to one embodiment of the present disclosure.

FIG. 2 is a representation of an embodiment of a laminate in accordancewith the present disclosure.

FIG. 3 is a microscopic image of a resin composition according to anembodiment of the present disclosure.

FIG. 4 is a microscopic image of a resin composition according to anembodiment of the present disclosure.

FIG. 5 is a microscopic image of a resin composition according to anembodiment of the present disclosure.

FIG. 6 is a microscopic image of a resin composition according to anembodiment of the present disclosure.

FIG. 7 is a microscopic image of a resin composition according to anembodiment of the present disclosure.

FIG. 8 is a microscopic image of a resin composition according to anembodiment of the present, disclosure.

FIG. 9 is a chart showing uptake of moisture over time as measured by %increase in weight for laminates according to the present disclosure anda comparator laminate.

FIG. 10 is a chart showing uptake of moisture over time as measured by %increase in weight for a laminate according to the present disclosure.

FIG. 11 is a chart showing flexural stress for laminates according tothe present disclosure, and a comparator laminate.

DETAILED DESCRIPTION

The following is a detailed description of the disclosure provided toaid those skilled in the art in practicing the present disclosure. Thoseof ordinary skill in the art may make modifications and variations inthe embodiments described herein without departing from the spirit orscope of the present disclosure.

Although any processes and materials similar or equivalent to thosedescribed herein can also be used in the practice or testing of thepresent disclosure, the preferred processes and materials are nowdescribed.

It must also be noted that, as used in the specification and theappended claims, the singular forms ‘a’, ‘an’ and ‘the’ include pluralreferents unless otherwise specified. Thus, for example, reference to‘resin’ may include more than one resins, and the like.

Throughout this specification, use of the terms ‘comprises’ or‘comprising’ or grammatical variations thereon shall be taken to specifythe presence of stated features, integers, steps or components but doesnot preclude the presence or addition of one or more other features,integers, steps, components or groups thereof not specificallymentioned.

The following definitions are included to provide a clear and consistentunderstanding of the specification and claims. As used herein, therecited terms have the following meanings. All other terms and phrasesused in this specification have their ordinary meanings as one of skillin the art would understand. Such ordinary meanings may be obtained byreference to technical dictionaries, such as Hawley's Condensed ChemicalDictionary 14th Edition, by R. J. Lewis, John Wiley & Sons, New York,N.Y., 2001.

Unless specifically stated or obvious from context, as used herein, theterm “about” is understood as within a range of normal tolerance in theart, for example within two standard deviations of the mean. ‘About’ canbe understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%,0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear fromcontext, all numerical values provided herein in the specification andthe claim can be modified by the term ‘about’.

Any processes provided herein can be combined with one or more of any ofthe other processes provided herein.

Ranges provided herein are understood to be shorthand for all of thevalues within the range. For example, a range of 1 to 50 is understoodto include any number, combination of numbers, or sub-range from thegroup consisting 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34,35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50.

As used herein, the term ‘cenosphere’ refers to spheres made largely ofsilica and alumina which are typically produced as a coal productionby-product in thermal power plants.

As used herein, the term ‘hollow glass microsphere’, also known as microballoons or glass bubbles, refers to hollow spheres of, for example, asodium silicate glass, typically prepared by ultrasonic spray pyrolysisof water glass.

As used herein the term ‘expanded glass aggregate’ refers to granularglass made from post-consumer glass.

Reference will now be made in detail to exemplary embodiments of thedisclosure. While the disclosure will be described in conjunction withthe exemplary embodiments, it will be understood that it is not intendedto limit the disclosure to those embodiments. To the contrary, it isintended to cover alternatives, modifications, and equivalents as may beincluded within the spirit and scope of the disclosure as defined by theappended claims.

The present disclosure is directed to resin compositions, compositematerials, fibreglass reinforced plastic, and laminates containing thefibreglass reinforced plastic. In particular, the present disclosure isdirected to composite materials containing cured polymer resin,graphene, milling media and milled fibreglass. The graphene is presentin a dispersed state which advantageously provides high strength to thecomposites.

Resin Composition

In embodiments, the resin composition according to the presentdisclosure comprises curable resin, graphene, milling media and milledglass fibres.

The resin composition may comprise:

-   -   a) from about 50 wt. % to about 80 wt. % of one or more curable        resins;    -   b) from about 0.1 wt. % to about 2.0 wt. % graphene;    -   c) from about 0.75 wt. % to about 35 wt. % of one or more        milling media; and    -   d) from about 3 wt. % to about 20 wt. % of milled fibreglass;        based on the total weight of resin composition.        Curable Resin

Any curable resin, or mixture of curable resins, typically used in themanufacture of fibreglass reinforced plastic may be utilized.

In some embodiments, the one or more curable resins comprise one or morecurable polyester resins, vinyl ester resins and epoxy resins. Thepolyester resins may comprise one or more of bisphenol A vinyl esterresin, terephthalate resin, terephthalate-NPG resin, isophthalate resin,isophthalate-NPG resin, orthophthalate resin, and orthophthalate-NPGresin. NPG refers to 2,2-dimethyl-1,3-propanediol (neopentyl glycol).

In some embodiments, a hybrid resin is used. Hybrid resins include, forexample, combinations of resins, such as combinations of the resin typeslisted above.

In some embodiments, a urethane acrylate modified resin is used.

In some embodiments, the curable resin comprises a mixture of a vinylester resin and least one other resin. In embodiments, the vinyl esterresin comprises greater than 10% by weight, based on the total weight ofresin in the resin composition, or greater than 20% by weight, orgreater than 30% by weight, or greater than 40% by weight, or greaterthan 50% by weight, or greater than 60% by weight, or greater than 70%by weight, or greater than 80% by weight, or greater than 90% by weight,based on the total weight of resin in the resin composition.

Graphene

In embodiments, the graphene has an average platelet size between about1 micron and about 100 micron, or between about 5 micron and about 50micron, or between about 10 micron and about 30 micron. The plateletsize may be determined by laser diffraction techniques.

Milling Media

Numerous materials may be suitable as milling material. Any materialthat is capable of dispersing the graphene through a milling process maybe utilised. Preferred milling materials are also substantiallychemically and/or mechanically inert during the manufacture of the resincomposition and subsequent composites and fibreglass reinforced resins.A unique feature of the present disclosure is that the milling media arenot removed from the resin composition after serving the purpose ofdispersing the graphene, but are retained in the subsequently formedcomposites and fibreglass reinforced resins. As one use of thefibreglass reinforced resins is in the manufacture of swimming pools,the milling media must remain inert for extended periods of time andshould not compromise the structural integrity of the fibreglassreinforced resin when exposed to water. Preferably, the milling materialis substantially insoluble in the resin composition. Preferred millingmedia are also substantially hydrophobic.

Preferred milling media have sufficiently high crush strength during themilling process such that their structural integrity is largelyretained.

Suitable milling media comprise one or both of silicon oxide andaluminium oxides. Exemplary milling media comprise one or more of hollowglass microspheres, cenospheres and expanded glass aggregate.

Without being bound by any particular theory, it is considered that thepresence of milling media such as microspheres assists in reducing waterand moisture uptake as well as assisting in dispersion of grapheneparticles.

In embodiments, the milling media have a diameter between about 30micron and about 150 micron.

Hollow Glass Microspheres

The hollow glass microspheres typically have a diameter from betweenabout 10 micron to about 300 micron, or from about 30 micron to about150 micron. The particle size of the hollow glass microspheres may bemeasured by sieving techniques or by laser diffraction. The glassmicrospheres may have a density between about 0.3 and about 0.6 g/ml.

Cenospheres

The cenospheres typically have a diameter from between about 20 micronto about 150 micron. In some embodiments, the cenospheres have adiameter from between about 30 micron to about 150 micron. The particlesize of the cenospheres may be measured by sieving techniques or bylaser diffraction. The cenospheres may have a density between about 0.4and about 0.8 g/ml.

Milled Fibreglass

The milled fibreglass may comprise E-Glass or E-CR corrosion resistantglass.

The milled fibreglass may have a fibre length between about 200 micronsand about 1000 microns.

In embodiments, the milled fibreglass may have an aspect ratio of about25-30:1.

The milled fibreglass may be treated with a sizing agent. The skilledperson would be well aware of sizing agents typically used in the art offibreglass reinforced plastic, such as, for example, silanes.

In embodiments the milled fibreglass may have a moisture content of lessthan 0.15% by weight.

Resin Composition Viscosity

In some embodiments, the viscosity of the resin composition is within arange enabling it to be sprayed.

Preferably the viscosity of the resin composition is between about 500cP (0.5 Pas) and about 6000 cP (6 Pas).

If necessary, the viscosity of the resin composition may be adjustedthrough the addition of a suitable thixotropic agent. Exemplarythixotropic agents include fumed silica, particularly hydrophobic fumedsilica.

FIG. 1 is a flow diagram illustrating one embodiment of a method formaking a resin composition according to the present disclosure.

In a first step, one or more curable resins (100), graphene (110) andone or more milling media (120) are added to batch mixer 1 (130) via,respectively, lines 105, 115 and 125. The order of addition is notcritical. The resulting mixture is then agitated to disperse thegraphene in the resin. Subsequently, the contents of mixer 1 aretransferred to batch mixer 2. Further resin (155) and further one ormore milling media (145) are added to mixer 2 via, respectively, lines160 and 150. The further one or more milling media (145) may be the sameor different to the one or more milling media (120). Mixer 2 isconnected to vacuum system via filter (180) and receiving tank (190) andthe mixture is further agitated under vacuum to degas the resincomposition. After mixing in mixer 2, milled fibreglass (165) is addedvia line 170. The contents of mixer 2 are transferred via line 200 tostorage vessel (205) for subsequent use in composite material andlaminate manufacture.

Optionally, in some embodiments, further additives, such as thixotropicagents, wetting agents and air release agents are added to mixer 2 priorto transfer to storage vessel (205). Preferably, these further additivesare added after addition of the further resin to mixer 2, but beforeaddition of the further milling media.

In some other embodiments, further additives, such as thixotropicagents, wetting agents and air release agents are added and dispersedinto the resin composition prior to vacuum application. On completion ofremoval of the air from the resin composite mixture the fluid istransferred to storage vessel (205). Preferably, these further additivesare added after addition of the further resin to mixer 2, but beforeaddition of the further milling media.

In the herein disclosed methods of making the resin composition themilling media act to disperse the graphene in the resin composition.When the resin composition is agitated they assist in dispersing thegraphene, however they also remain in the resin composition.

In some embodiments, a mixture containing graphene, a curable resin andone or more milling media are mixed for a period of at least 30 minutes,for example the mixture may be mixed for a period in the range of from30 minutes to 1 hour, prior to admixing with other components (e.g.milled fibreglass, further resin, further milling media).

Preferred milling media are inert and insoluble in the resin compositionand inert and insoluble in the cured composite material. This isimportant when the resin composition is utilised in the manufacture oflaminate structure for a fibreglass swimming pool. It was found thathollow glass microspheres and cenospheres were suitable to be used inthe milling process. These materials did not induce osmotic blisteringand potential early degradation of the fibreglass laminate when thelaminate was exposed to water for extended periods of time, as is thecase of a swimming pool.

In embodiments, the milling media also enhance the physical strength andchemical and water resistance of the fibreglass laminate while alsoperforming the function of milling media to disperse the graphene in theresin composition.

Preferably the milling media should have sufficient crush strength toprevent excessive crushing during the milling and spraying processes.

In embodiments, the milling media added to mixer 1 may comprise one ormore of hollow glass microspheres, cenospheres and expanded glassaggregate.

In embodiments, the milling media added to mixer 2 may comprise one ormore of hollow glass microspheres, cenospheres and expanded glassaggregate.

In some preferred embodiments, the milling media added to mixer 1 maycomprise hollow glass microspheres.

In some preferred embodiments, the milling media added to mixer 2 maycomprise cenospheres.

A preferred mixer for mixer 1 is equipped with mixing blades thatminimises crushing and break down of the milling media.

In an embodiment, about 15 wt. % of the total resin amount of the finalresin composition is added to mixer 1 along with the graphene andmilling media. The mixture is agitated preferably with a maximum mixerspeed of 100 rpm. It is preferred that high shear is avoided so as tominimise crushing of the milling media. Mixing is continued until thegraphene appears well dispersed.

In an embodiment, graphene is mixed in mixer 1 with a portion of theresin and a portion of the milling media (e.g. at high concentration)until the graphene is at least partially dispersed. An amount of themixture is then transferred into mixer 2, the remainder of the resin andmilling media are added to mixer 2, and the components are mixed untilthe graphene has been sufficiently dispersed and agglomerates reduced tosmaller particles. For example, the mixing period in mixer 2 may beabout 30 minutes.

Preferably the milling media are hydrophobic as they are retained withinthe fibreglass reinforced resin and subjected to the long-term watervapour transpiration through the laminate structure.

On completion of the initial dispersion in mixer 1 the fluid containingthe resin, graphene and milling media are transferred into mixer 2 whichis designed to operate under vacuum.

At this time, any required accelerators, promoters, inhibitors, airrelease agents, wetting agents and low styrene emission additives may beadded into the resin mix.

In embodiments, further resin is transferred into mixer 2 via an inletport. At this point, the mixer may be agitated at relatively low speed,for example in the range 50-100 rpm, until the resin fully covers themixing blades.

In embodiments, mixer 2 contains internal baffles to prevent the fluidfrom circulating at excessive speed and to disrupt the fluid flow andadd turbulence to the milling process.

A preferred mixer forces fluid against the baffles of the mixer andagitates the milling media against the graphene. Additionally, apreferred mixer forces the fluid downward from top to bottom thusincreasing turbulence within the mixer. If desired, the speed of themixer may be varied, e.g. increased to aid dispersion and to continueagitation of the fluid.

After addition of the further resin to mixer 2, a thixotropic agent,such as hydroscopic fumed silica, if required, may be added to adjustthe viscosity of the mixture. At this time, vacuum may be applied tomixer 2. Preferably, vacuum is applied following completion of themixing process.

In embodiments, the mixing speed is increased and further milling mediaadded. The total resin composition comprising, resin, graphene andmilling media is continued to be mixed until the graphene is fullydispersed within the composition.

Mixer 2 represents the secondary stage of the dispersing process. Themilling media initially disperse the graphene in the smaller resinamount in mixer 1, enabling further dispersion into the total volume ofresin when further milling media and resin are added in mixer 2.

The combined action of agitation, turbulence and shear allow the millingmedia to shear and disperse the graphene into the resin composition.Preferably, the final dispersion of the graphene into the resin andmilling media occurs in mixer 2.

When the graphene is fully dispersed in the resin the milled fibreglassis added.

The milled fibreglass is added to increase the flexural strength and theflexural modulus of the fibreglass reinforced resin.

It was observed that the addition of milled fibreglass not onlyincreased the flexural strength and flexural modulus of the curedcomposite material, it allowed the resin composition to retain itsintegrity such that agglomeration of components was minimised withinnormal expected manufacturing time restraints, and assists with theretention of the milling media in suspension. Accordingly, aconsistently even, homogenous, smooth and sprayable resin compositionmay be prepared.

For use in the spray process it is important that the resin compositionis able to be sprayed with continuous fibreglass rovings. It must beable to be laid down evenly and to be able to be rolled out through thesprayed continuous fibreglass rovings and to be able to wet out thefibreglass.

It was observed that during the milling process, in the absence ofapplied vacuum, a significant quantity of air may be entrapped withinthe resin composition. By comparing the measured density of the resincomposition to the calculated density, the measured density was lessthan expected.

By applying vacuum to the resin composition, the measured densityincreased so as to be comparable to the calculated density. This wasfound to be advantageous as it resulted in composite materials with lessentrapped micro voids of air.

In embodiments, vacuum may be applied to the resin composition for about10 minutes to about 1 hour. In some embodiments, vacuum may be appliedat the completion of the manufacture of the resin composition tomaximise the removal of air from the composition and minimise the numberof microvoids of air.

Further Additives

Further additives, such as one or more accelerators, promoters,inhibitors, air release agents, wetting agents, silanes, and low styreneemission additives may be added during or after production of the resincomposition.

In some embodiments, one or more silanes is added, more particularly anorganosilane. The silanes act as wetting agents. They can be used toimprove the physical characteristics of the resin compositions. Withoutbeing bound by any particular theory, it is considered that the silanescan treat the surface of asicular silicon-based fibres, modifying thesurface of the fibres by affecting properties such as zeta potentialand/or hydrophobicity. It is considered that these properties can inturn modify the chemistry of the interphase, and affect the performanceof the fibre reinforced composites, particularly those with very shortfibres.

Examples of silanes include vinyltrimethoxysilane (VTMS),phenyltrimethoxysilane (PTMS), aminopropyltrimethoxysilane (APTMS),(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPTMS),N-cyclohexyl-3-aminopropyltrimethoxysilane (CHAPTMS),3-aminopropyltriethoxysilane (APTES),N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane (AEAPMDMS),N-(2-aminoethyl)-3-aminopropylmethoxypolysiloxane (AEAPMPS),3-methacryloxypropyltrimethoxysilane (MAOPTMS),methacryloxymethylmethyldimethoxysilane (MAOMMDMS),methacryloxymethyltrimethoxysilane (MAOMTMS),glycidoxypropyltrimethoxysilane (GOPTMS),4-glycidoxypropyltrimethoxysilane, 6-glycidoxypropyltrimethoxysilane andoctyltriethoxysilane (OTES).

In some embodiments, 3-methacryloxypropyltrimethoxysilane isincorporated into the resin composition.

Where a silane is used, it is typically added in an amount in the rangeof from 0.5 wt % to 5 wt % of the resin composition, or from 1 wt % to 4wt %, or from 0.5 wt % to 1 wt %, or from 1 wt % to 2 wt %, or from 2 wt% to 3 wt %, or from 3 wt % to 4 wt %, or from 4 wt % to 5 wt %.

Where a further additive or additives is/are added, in some embodiments,the further additive(s) is/are added to mixer 2 prior to adding themilling media and the milled glass. Where a further resin is added, insome embodiments where a further additive or additives is/are added, thefurther additive(s) is/are added to mixer 2 prior to adding the furtherresin.

Preferred promoters include metal promoters such as one or more of zincoctoate, potassium octoate and cobalt octoate. Other promoters that cansuitably be used include, but are not limited to, SHEN catalyst PC-6 anddimethyl aniline. Defoaming agents and wetting agents typically used inthe art may be added as required.

Composite Material

The resin composition may be cured to provide the composite materialaccording to the present disclosure.

Fibreglass Reinforced Resin

The resin composition may be combined with further fibreglass and curedto provide the herein disclosed fibreglass reinforced resin.

In embodiments, the further fibreglass comprises fibreglass rovings withan average cut length from about 5 mm to about 20 mm.

The fibreglass rovings may comprise E-Glass or 6-ECR corrosion resistantglass.

The fibreglass rovings may be treated with a sizing agent. The skilledperson would be well aware of sizing agents typically used in fibreglassreinforced plastic, such as, for example, silanes.

In embodiments, the fibreglass rovings may have a moisture content ofless than 0.15% by weight

In embodiments, the weight ratio of resin composition to fibreglassrovings may be between about 2.1 and about 4:1, depending on thestructural composition of the finished laminate. In some embodiments,the weight ratio of resin composition to fibreglass rovings may bebetween about 2:1 and about 2.5:1. In some embodiments, the weight ratioof resin composition to fiberglass rovings may be between about 2:1 andabout 3:1. In alternate embodiments, the weight ratio of resincomposition to fibreglass rovings may be between about 3:1 and about4:1.

Laminates

The present disclosure also provides laminate structures comprising oneor more layers of fibreglass reinforced resin and optionally one or morelayers of another material.

In embodiments, the laminates may comprise one, or two, or three, orfour, or five, or more layers of the graphene-containing fibreglassreinforced resin. The layers of fibreglass reinforced resin may be thesame or may be different. For example, the layers of fibreglassreinforced resin may comprise different cured resins and/or differentrelative amounts of resin, graphene, milling media, milled fibreglass,and fibreglass rovings, depending on the particular end use.

For the construction of a swimming pool or spa pool, one or more layersof gelcoats may be present as outer layers (exposed to water). Thesegelcoats may comprise additives such as promoters and inhibitors.

In some embodiments, the laminate contains one or more layers offibreglass reinforced resin, and one or more gelcoat layers. In someembodiments, the laminate comprises two, three, four or fivegraphite-containing fibreglass reinforced resin layers, and one, two orthree gelcoat layers. In some embodiments, the laminate comprises fourgraphite-containing fibreglass reinforced resin layers, and two gelcoatlayers.

In some embodiments, the laminate contains multiple layers (e.g. two,three, four or five) of fibreglass reinforced resin. In someembodiments, the laminate does not comprise a gelcoat layer.

Preferred promoters include metal promoters such as one or more of zincoctoate, potassium octoate and cobalt octoate. Other promoters that cansuitably be used include, but are not limited to, SHEN catalyst PC-6 anddimethyl aniline. Defoaming agents may be added as required.

At least one UV inhibitor and/or absorber or a light stabiliser may alsobe added to the gelcoats. In embodiments, two UV absorbers may be added,known commercially under the trade marks Tinuvin™ and Chimassorb™, eachproduced by BASF™ Specialty Chemicals Inc. Preferred blends are Tinuvin™384-2 and Chimassorb™ 1 19FL. Particularly preferred blends are Tinuvin™400 and Tinuvin™ 123. These UV absorbers and stabilisers act to improvethe resistance of the gelcoats to UV exposure failures such asdiscoloration, cracking and fading.

In an exemplary embodiment of the manufacture of a laminate according tothe present disclosure, a gelcoat layer or layers are sprayed onto apolished fibreglass mould and allowed to cure until trafficable.

Within about 30 minutes of the gelcoat curing sufficiently to allow anoperator to walk on the floor of the gelcoat treated mould, a resincomposition according to any of the embodiments of the presentdisclosure is sprayed onto the outer layer of the gelcoat using achopper gun, for example using a Magnum Venus P31 chopper gun with sprayboom.

In embodiments, the resin composition is first sprayed evenly over asection to be sprayed to wet out the area. Typically, wet film thicknessshould not exceed 0.5 mm.

Next, an appropriate thickness of resin composition and continuousfibreglass rovings is sprayed onto the wetted-out area of the mould.After 2-3 minutes to allow the resin to wet through, fibreglass rollingis commenced to remove air from the deposited resin composition andfibreglass.

The preferred length of the fibre to be deposited with the resin streamis about 12 mm. Corrosion resistant glasses, such as Jushi E6-ECR13 orCTG ER240-T132D TEX 2400 continuous roving, is a preferred fibreglass.Adjustment of the roller speed in the chopper gun may be required tospray the correct proportion of the resin composition with the choppedcontinuous fibreglass to achieve the desired final resin to glass ratio.

As the resin mix is not transparent due to the presence of graphene andthe milling media present in the resin composition it is important toensure that any air is removed. Cross sectional analysis under amicroscope may be utilised to ensure the correct thicknesses have beenapplied and that the finished layer has been sufficiently rolled out toremove all visible air voids.

The resin composition and fibreglass layer are allowed to cure beforethe next application.

The process of spraying resin composition and chopped fibreglass may berepeated one or more times so as to afford multiple layers of fibreglassreinforced resin.

The thickness and composition of each fibreglass reinforced resin layermay be the same or different. For example, the relative amounts ofresin, graphene, milling media, milled fibreglass and fibreglass rovingsmay be the same or different in each of the layers. Additionally, oralternatively, the nature of the resins may be the same or different.

After the final structural layer has been allowed to cure, an outersurface layer may be sprayed to a minimum thickness of about 0.35 mm toseal off any protruding fibres and prevent the ingress of moisture intothe rear of the swimming pool laminate.

A typical laminate may for example have a thickness in the range of from6 mm to 12 mm, e.g. about 10 mm.

The finished swimming pool is then allowed to cure on the mould forabout 24 hours prior to demoulding.

As soil conditions vary from location to location it is possible, usingthe composites of the present disclosure, to design and manufacture aswimming pool to withstand any additional loads and especially thosefrom reactive clay, hydrostatic pressure and hydrodynamic pressure.

An example of a laminate in accordance with the present disclosure isprovided in FIG. 2 . The laminate has the following layers: A) firstgelcoat layer; B) second gelcoat layer; C) first chemical resistant andstructural layer of fibreglass reinforced resin containing graphene, andfibreglass roving; D) layer of fibreglass reinforced resin containinggraphene—syntactic core; E) second chemical resistant and structurallayer of fibreglass reinforced resin containing graphene, and fibreglassroving; and F) layer of fibreglass reinforced resin containinggraphene—water and chemical resistant outer composite layer. Such alaminate may find use in the manufacture of, for example, swimmingpools.

Gelcoat layer A) may for example be pigmented or clear, and/or containparticles. Typically Layer A) comprises a resin such as, for example abisphenol A vinyl ester resin, terephthalate resin, terephthalate-NPGresin, isophthalate resin, isophthalate-NPG resin, orthophthalate resin,orthophthalate-NPG resin, urethane acrylate modified resin, and hybridresins or combinations of the above. This gelcoat layer is typicallysprayed on, e.g. with a wet film thickness in the range of from 0.45 mmto 0.75 mm, for example from 0.6 mm to 0.75 mm. In some embodiments,layer A) has a thickness of about 0.5 mm, or about 0.55 mm, or about 0.6mm, or about 0.65 mm, or about 0.7 mm, or about 0.75 mm.

Gelcoat layer B) may for example be pigmented or clear, and/or containpanicles, but typically is pigmented and/or contains particles. Layer B)may for example comprise a resin such as, for example a bisphenol Avinyl ester resin, terephthalate resin, terephthalate-NPG resin,isophthalate resin, isophthalate-NPG resin, orthophthalate resin,orthophthalate-NPG resin, and/or urethane acrylate modified resin. Insome embodiments, a bisphenol A vinyl ester resin is used for layer B).Layer B) provides chemical and water-resistant properties, and can alsobe used to provide colour to the laminate. Typically, after wet sprayingand curing of gelcoat layer A) until trafficable, layer B) is sprayedonto the first, e.g. with a wet film thickness in the range of from 0.45mm to 0.75 mm, or from 0.5 mm to 0.75 mm, or about 0.5 mm, or about 0.55mm, or about 0.6 mm, or about 0.65 mm, or about 0.7 mm, or about 0.75mm.

Layer C) is a structural layer having chemical resistance properties andcomprises a resin, dispersed graphene, milling media and milledfibreglass. For example, the resin may be one or more of a bisphenol Avinyl ester resin, terephthalate resin, terephthalate-NPG resin,isophthalate resin, isophthalate-NPG resin, orthophthalate resin andorthophthalate-NPG resin. The milling media may for example becenospheres and or hollow glass microspheres. The layer may for examplealso contain fiberglass roving, such as Tex2400 continuous fibreglassroving. Typically, the total resin to fibreglass weight ratio in layerC) is in the range of from 2.0-2.5:1. Typically, a compositioncontaining the resin, dispersed graphene, milling media and milledfibreglass is sprayed onto gelcoat layers A) and B) with fibreglassroving (e.g. Tex2400 continuous fibreglass roving. Air is rolled out,and the laminate allowed to gel/cure until trafficable. Typicalthicknesses may be in the range of from 2.0 to 4.0 mm (e.g. for swimmingpool applications, depending on engineering specifications), for exampleabout 2.0 mm, or about 2.5 mm, or about 3.0 mm, or about 3.5 mm, orabout 4.0 mm.

Layer D) is a syntactic core, and comprises a resin, graphene, millingmedia and milled fibreglass. For example, the resin may be one or moreof a bisphenol A vinyl ester resin, terephthalate resin,terephthalate-NPG resin, isophthalate resin, isophthalate-NPG resin,orthophthalate resin and orthophthalate-NPG resin. The milling media mayfor example be cenospheres and/or hollow glass microspheres. Layer D) istypically sprayed on to layer C), e.g. with continuous passes, until thedesired thickness is reached. Typical thicknesses are in the range offrom 2.0 mm to 4.2 mm, or from 2.0 mm to 4.0 mm, or about 2.0 mm, about2.5 mm, about 3.0 mm, about 3.5 mm, or about 4.0 mm. Whilst in someembodiments the laminate comprises layer D), in other embodiments layerD) may be omitted.

Layer E) is a further structural layer having chemical resistanceproperties, and comprises a resin, dispersed graphene, milling media andmilled fibreglass. For example, the resin may be one or more of abisphenol A vinyl ester resin, terephthalate resin, terephthalate-NPGresin, isophthalate resin, isophthalate-NPG resin, orthophthalate resinand orthophthalate-NPG resin. The milling media may for example becenospheres and/or hollow glass microspheres. Typically, the resin tofibreglass weight ratio may be in the range of from 2.0-2.5:1. The layermay for example also contain fiberglass roving, such as Tex2400continuous fibreglass roving. The basic components of layer E) are thesame as in layer C) (e.g. it also contains a resin, graphene, millingmedia, milled fibreglass, and fibreglass roving), however the specificcomponents (e.g. the resin used) may be the same or different. The ratioof materials used (e.g. the weight ratio of resin to fibreglass) may bethe same or different to that used in layer C). Typically, a compositioncontaining the resin, dispersed graphene, milling media and milledfibreglass is sprayed onto the preceding layers with fibreglass roving(e.g. Tex2400 continuous fibreglass roving. Air is rolled out, and thelaminate allowed to gel/cure until trafficable. Typical thicknesses maybe in the range of from 2.0 to 4.0 mm (e.g. for swimming poolapplications, depending on engineering specifications), for exampleabout 2.0 mm, or about 2.5 mm, or about 3.0 mm, or about 3.5 mm, orabout 4.0 mm. The layer thickness is typically the same as or similar tothe thickness of layer C).

Layer F) comprises a resin, graphene, milling media and milledfibreglass. The resin and milling media may for example be thosedescribed above for other layers of the laminate. Layer F) provideswaterproofing properties, acting as a waterproof barrier. Layer F) issprayed over the other layers providing a surface layer. Typicalthicknesses for layer F) are in the range of from 0.3 mm to 0.4 mm, forexample about 0.3 mm, about 0.35 mm or about 0.4 mm.

Another example of a laminate in accordance with the present disclosureis a laminate containing layers A), B), C), E) and F) as discussedabove, but omitting layer D).

The contents of all references and published patents and patentapplications cited throughout the application arc hereby incorporated byreference.

EXAMPLES Example 1: Resin Composition

Graphene-containing resin compositions according to the presentdisclosure were prepared. A mixture of graphene, styrene monomer, milledfibreglass, and milling media (cenospheres and hollow glassmicrospheres) was mixed using a rotor and stator mixing head. Samples ofthe composition were taken at different time points and subjected tomicroscopic examination.

FIGS. 3-5 respectively show microscopic images of the compositionfollowing mixing for 3 minutes, 15 minutes and 30 minutes. As can beseen, the extent of dispersion increases with increased mixing time.

Further examples of resin compositions are provided in FIGS. 6 to 8 .FIGS. 6 and 7 show microscopic images of resin compositions containingmilled fibreglass, graphene, curable resin (styrene monomer) and millingmedia (cenospheres and hollow glass microspheres). FIG. 8 shows amicroscopic image of graphene dispersed in a curable resin (styrenemonomer) with cenospheres and hollow glass microspheres after mixing for30 minutes, prior to addition of milled fibre glass.

Example 2: Laminate Moisture Uptake

Three panels were subjected to full water submersion at 110° C. at 100kPa in a pressure vessel and tested for extent of moisture absorption asdetermined by % increase in weight, measuring at appropriate intervalsover a 140-170 hour period. Three panels were tested: 1) anon-graphene-containing laminate containing a terephthalate-NPG resinand milled fibreglass; 2) a panel formed of a graphene-containingfibreglass reinforced resin containing a terephthalate-NPG resin, milledfibreglass, and dispersed graphene; and 3) a panel formed of a laminateincluding a layer of a graphene-containing fibreglass reinforced resin(containing a terephthalate-NPG resin, milled fibreglass, and dispersedgraphene). The results are shown in FIG. 9 .

As can be seen from FIG. 9 , there was significantly less water uptake,as water vapour, in the graphene-containing panels. Thegraphene-containing panels had up to about 4% increase in weight overthe course of the experiment, compared with 10% for the comparatorswimming pool laminate.

Example 3: Laminate Moisture Uptake

A panel formed of a laminate of a graphene-containing fibreglassreinforced resin according to the present disclosure containing aterephthalate-NPG resin, dispersed graphene, and milled fibreglass, anda gelcoat, was subjected to full water submersion at 110° C. at 100 kPain pressure vessel and tested for extent of moisture absorption asdetermined by % increase in weight over a 90 hour period. The resultsare shown in FIG. 10 .

As can be seen from FIG. 10 , the laminate showed very low levels ofmoisture uptake (less than 1%) over the course of the experiment.

Example 4: Fibreglass Reinforced Plastic Flexural Strength

Flexural strength was measured for panels containing dispersed graphene(5 mm thick panels made from terephthalate-NPG resin with chopped strandfibreglass mat, resin to glass ratio of 2.5:1, dispersed graphene, resincatalysed using 2% of a Butanox M50 catalyst and rolled through thechopped strand mat) and a comparator containing no graphene. Thecomparator (sample 0) contained 0% graphene. 3 types of cured resincomposition according to the present disclosure were tested,respectively containing graphene of average platelet size 20 micron(samples 1a-1d), 10 micron (samples 2a-2d), or 5 micron (samples 3a-3d),sold under the brand names PureGRAPH® 20, PureGRAPH® 10 and PureGRAPH®5). The resin compositions contained either 0.5% by weight dispersedgraphene (samples 1a, 2a, 3a), 1% by weight dispersed graphene (samples1b, 2b, 3b), 1.5% by weight dispersed graphene (samples 1c, 2c, 3c) or3% by weight dispersed graphene (samples 1d, 2d, 3d). The results areshown in the table below.

Mean Mean Graphene Flexural Flexural Mean Peak Flexural FlexuralConcentration Modulus Modulus Peak Load Std Stress Stress Std Sample (%)(Mpa) Std Dev Load (N) Dev (Mpa) Dev. 0   0% 3717 227 431 42 163 4.4 1a0.5% 7547 161 547 27 204 11.3 1b 1.0% 7849 637 561 57 219 7.8 1c 1.5%7618 193 488 56 176 15.6 1d 3.0% 6181 141 457 19 174 9 2a 0.5% 202 1.92b 1.0% 211 8.0 2c 1.5% 203 4.1 2d 3.0% 211 6.1 3a 0.5% 6838 397 18415.9 3b 1.0% 6991 143 569 22 220 8 3c 1.5% 7495 377 210 9.7 3d 3.0% 7352512 203 14.0

The flexural stress results are also shown in FIG. 11 . The flexuralstress results were higher for the samples according to the presentdisclosure than for the comparator sample.

EMBODIMENTS

Embodiment 1: A resin composition, said resin composition comprising:

-   -   a) one or more curable resins;    -   b) graphene;    -   c) one or more milling media; and    -   d) milled fibreglass.

Embodiment 2: A resin composition according to embodiment 1, wherein theone or more milling media are hydrophobic.

Embodiment 3: A resin composition according to embodiment 1 orembodiment 2, wherein the one or more milling media are insoluble in theresin composition.

Embodiment 4: A resin composition according to any one of embodiments 1to 3, wherein the one or more milling media are inert.

Embodiment 5: A resin composition according to any one of embodiments 1to 4, wherein the crushing strength of the one or more milling media isgreater than about 2000 psi (13.79 MPa), or greater than about 3000 psi(20.70 MPa), or greater than about 4000 psi (27.58 MPa).

Embodiment 6: A resin composition according to any one of embodiments 1to 4, wherein the crushing strength of the one or more milling media isbetween about 2000 psi (13.79 MPa) and about 4000 psi (27.58 MPa).

Embodiment 7: A resin composition according to any one of embodiments 1to 6, wherein the one or more milling media have a Mohs hardness ofgreater than about 4, or greater than about 5, or greater than about 6.

Embodiment 8: A resin composition according to any one of embodiments 1to 6, wherein, the one or more milling media have a Mohs hardness fromabout 4 to about 7, or from about 5 to about 7.

Embodiment 9: A resin composition according to any one of embodiments 1to 8, wherein the one or more milling media comprise one or more ofsilicon oxides or aluminium oxides.

Embodiment 10: A resin composition according to any one of embodiments 1to 9, wherein the one or more milling media comprise one or more ofhollow glass microspheres, cenospheres and expanded glass aggregate.

Embodiment 111: A resin composition according to any one of embodiments1 to 10 comprising:

-   -   a. from about 50 wt. % to about 80 wt. % of one or more curable        resins;    -   b. from about 0.1 wt. % to about 2.0 wt. % graphene;    -   c. from about 0.75 wt. % to about 35 wt. % of milling media; and    -   d. from about 3 wt. % to about 20 wt. % of milled fibreglass;    -   based on the total weight of resin composition.

Embodiment 12: A resin composition according to any one of embodiments 1to 11, wherein the one or more curable resins comprise one or morecurable polyester resins, vinyl ester resins and epoxy resins.

Embodiment 13: A resin composition according to any one of embodiments 1to 12, wherein the one or more curable resins comprise one or more ofbisphenol. A vinyl ester resin, terephthalate resin, terephthalate-NPGresin, isophthalate resin, isophthalate-NPG resin, orthophthalate resin,and orthophthalate-NPG resin.

Embodiment 14: A resin composition according to any one of embodiments 1to 13, wherein the one or more curable resins comprise a vinyl esterresin and terephthalate-NPG resin.

Embodiment 15: A resin composition according to any one of embodiments 1to 14, wherein the one or more curable resins comprise a urethaneacrylate modified resin.

Embodiment 16: A resin composition according to any one of embodiments12 to 14, wherein the vinyl ester resin comprises greater than 10% byweight, based on the total weight of resin in the resin composition, orgreater than 20% by weight, or greater than 30% by weight, or greaterthan 40% by weight, or greater than 50% by weight, or greater than 60%by weight, or greater than 70% by weight, or greater than 80% by weight,or greater than 90% by weight, based on the total weight of resin in theresin composition.

Embodiment 17: A resin composition according to any one of embodiments 1to 16, wherein the graphene has an average platelet size between about 1micron and about 100 micron, or between about 5 micron and about 50micron, or between about 10 micron and about 30 micron.

Embodiment 18: A resin composition according to any one of embodiments10 to 17, wherein the hollow glass microspheres have a diameter betweenabout 30 micron and about 150 micron.

Embodiment 19: A resin composition according to any one of embodiments10 to 18, wherein the cenospheres have a diameter between about 20micron and about 150 micron.

Embodiment 20: A resin composition according to any one of embodiments10 to 19, wherein the resin composition comprises hollow glassmicrospheres, cenospheres or both hollow glass microspheres andcenospheres.

Embodiment 21: A resin composition according to any one of embodiments 1to 20, wherein the milled fibreglass has a fibre length between about200 microns and about 1000microns.

Embodiment 22: A resin composition according to any one of embodiments 1to 21, wherein the milled fibreglass further comprises a sizing agent.

Embodiment 23: A resin composition according to any one of embodiments 1to 22 further comprising one or more thixotropic agents.

Embodiment 24: A resin composition according to embodiment 23, whereinthe thixotropic agent comprises fumed silica, preferably hydrophobicfumed silica.

Embodiment 25: A resin composition according to any one of embodiments 1to 24, further comprising one or more accelerators, promoters,inhibitors, air release agents, wetting agents and silanes.

Embodiment 26: A resin composition according to any one of embodiments 1to 25, wherein the resin composition comprises a silane which is3-methacryloxypropyltrimethoxysilane.

Embodiment 27: A resin composition according to any one of embodiments 1to 26, wherein the viscosity of the resin composition is from about 500cP (0.5 Pas) to about 6000 cP (6 Pas).

Embodiment 28: A composite material, said composite material comprising:

-   -   a. one or more cured resins;    -   b. graphene;    -   c. one or more milling media; and    -   d. milled fibreglass.

Embodiment 29: A composite material according to embodiment 28, whereinthe one or more milling media are hydrophobic.

Embodiment 30: A composite material according to embodiment 28 orembodiment 29, wherein the one or more milling media are insoluble inthe composite material.

Embodiment 31: A composite material according to any one of embodiments28 to 30, wherein the one or more milling media are inert.

Embodiment 32: A composite material according to any one of embodiments28 to 31, wherein the crushing strength of the one or more milling mediais greater than about 2000 psi (13.79 MPa), or greater than about 3000psi (20.70 MPa), or greater than about 4000 psi (27.58 MPa).

Embodiment 33: A composite material according to any one of embodiments28 to 31, wherein the crushing strength of the one or more milling mediais between about 2000 psi (13.79 MPa) and about 4000 psi (27.58 MPa).

Embodiment 34: A composite material according to any one of embodiments28 to 33, wherein the one or more milling media have a Mohs hardness ofgreater than about 4, or greater than about 5, or greater than about 6.

Embodiment 35: A composite material according to any one of embodiments28 to 33, wherein, the one or more milling media have a Mohs hardnessfrom about 4 to about 7, or from about 5 to about 7.

Embodiment 36: A composite material according to any one of embodiments28 to 35, wherein the one or milling media comprise one or more ofsilicon oxides or aluminium oxides.

Embodiment 37: A composite material according to any one of embodiments28 to 36, wherein the one or more milling media comprise one or more ofhollow glass microspheres, cenospheres and expanded glass aggregate.

Embodiment 38: A composite material according to any one of embodiments28 to 37 comprising:

-   -   a. from about 50 wt. % to about 80 wt. % of one or more cured        resins;    -   b. from about 0.1 wt. % to about 2.0 wt. % graphene;    -   c. from about 0.75 wt. % to about 35 wt. % of one or more        milling media; and    -   d. from about 3.0 wt. % to about 20 wt. % of milled fibreglass;        based on the total weight of the composite material.

Embodiment 39: A composite material according to any one of embodiments28 to 38, wherein the one or more cured resins comprise one or morecured polyester resins, vinyl ester resins and epoxy resins.

Embodiment 40: A composite material according to any one of embodiments28 to 39, wherein the one or more cured resins comprise one or more ofbisphenol A vinyl ester resin, terephthalate resin, terephthalate-NPGresin, isophthalate resin, isophthalate-NPG resin, orthophthalate resin,and orthophthalate-NPG resin.

Embodiment 41: A composite material according to any one of embodiment28 to 40, wherein the one or more cured resins comprise a vinyl esterresin and terephthalate-NPG resin.

Embodiment 42: A composite material according to any one of embodiments28 to 41, wherein the cured vinyl ester is present in an amount ofgreater than 10% by weight, based on the total weight of cured resin inthe composite material, or greater than 20% by weight, or greater than30% by weight, or greater than 40% by weight, or greater than 50% byweight, or greater than 60% by weight, or greater than 70% by weight, orgreater than 80% by weight, or greater than 90% by weight, based on thetotal weight of cured resin in the composite material.

Embodiment 43: A composite material according to any one of embodiments28 to 40, wherein the one or more curable resins comprise a urethaneacrylate modified resin.

Embodiment 44: A composite material according to any one of embodiments28 to 43, wherein the graphene has an average platelet size betweenabout 1 micron and about 100 micron, or between about 5 micron and about50 micron, or between about 10 micron and about 30 micron.

Embodiment 45: A composite material according to any one of embodiments37 to 44, wherein the hollow glass microspheres have a diameter betweenabout 30 micron and about 150 micron.

Embodiment 46: A composite material according to any one of embodiments37 to 45, wherein the cenospheres have a diameter between about 30micron and about 150 micron.

Embodiment 47: A composite material according to any one of embodiments28 to 46, wherein the composite material comprises both hollow glassmicrospheres and cenospheres.

Embodiment 48: A composite material according to any one of embodiments28 to 47, wherein the milled fibreglass has a fibre length between about200 microns and about 1000 microns.

Embodiment 49: A composite material according to any one of embodiments28 to 48, wherein the milled fibreglass further comprises a sizingagent.

Embodiment 50: A composite material according to any one of embodiments28 to 49 further comprising one or more thixotropic agents.

Embodiment 51: A composite material according to embodiment 50, whereinthe thixotropic agent comprises fumed silica, preferably hydrophobicfumed silica.

Embodiment 52: A fibreglass reinforced resin comprising the compositematerial according to any one of embodiments 28 to 51 and furtherfibreglass.

Embodiment 53: A fibreglass reinforced resin according to embodiment 52,wherein the further fibreglass has a fibre length greater than about 1mm, or greater than about 5 mm, or greater than about 8 mm.

Embodiment 54: A fibreglass reinforced resin according to embodiment 52or embodiment 53, wherein the fibreglass reinforced resin has a flexuralstrength greater than about 124 MPa, or greater than about 130 MPa, orgreater than about 140 MPa, or greater than about 150 MPa, or greaterthan about 160 MPa.

Embodiment 55: A fibreglass reinforced resin according to embodiment 52or embodiment 53, wherein the fibreglass reinforced resin has a flexuralstrength between about 124 MPa and about 160 MPa, or between about 140MPa and about 160 MPa.

Embodiment 56: A fibreglass reinforced resin according to any one ofembodiments 52 to 55, wherein the fibreglass reinforced resin has aflexural modulus greater than about 7,700 MPa, or greater than about8,000 MPa, or greater than about 8,500 MPa, or greater than about 9,000MPa, or greater than about 9,500 MPa, or greater than about 10,000 MPa.

Embodiment 57: A fibreglass reinforced resin according to any one ofembodiments 52 to 55, wherein the fibreglass reinforced resin has aflexural modulus between about 7,700 MPa and about 10,000 MPa, orbetween about 8,500 MPa and about 10,000 MPa.

Embodiment 58: A fibreglass reinforced resin according to any one ofembodiments 52 to 57, wherein the fibreglass reinforced resin has atensile strength greater than about 100 MPa, or greater than about 110MPa, or greater than about 120 MPa, or greater than about 130 MPa, orgreater than about 140 MPa.

Embodiment 59: A fibreglass reinforced resin according to any one ofembodiments 52 to 57, wherein the fibreglass reinforced resin has atensile strength between about 100 MPa and about 140 MPa, or betweenabout 110 MPa and about 140 MPa.

Embodiment 60: A laminate comprising one or more layers of fibreglassreinforced resin according to any one of embodiments 52 to 59.

Embodiment 61: A laminate according to embodiment 60, further comprisingone or more layers of another material, for example one or more layersof a polymer or mixture of polymers.

Embodiment 62: A laminate according to embodiment 61, wherein the one ormore other layers comprises one or more gelcoats.

Embodiment 63: A laminate according to embodiment 62, wherein thegelcoat comprises one or more polyesters or vinyl esters.

Embodiment 64: A swimming pool or spa pool comprising a laminateaccording to any one of embodiments 60 to 63.

Embodiment 65: A method of preparing a resin composition according toany one of embodiments 1 to 27, said method comprising:

-   -   a. forming a mixture of one or more curable resins, graphene,        and one or more milling media;    -   b. agitating the mixture to disperse the graphene; and    -   c. adding milled fibreglass.

Embodiment 66: A method according to embodiment 65, further comprisingadding one or more thixotropic agents.

Embodiment 67: A method according to embodiment 65 or embodiment 66,further comprising degassing the resin composition.

Embodiment 68: A method of preparing a resin composition according toany one of embodiments 1 to 27, said method comprising:

-   -   a. forming a mixture of one or more curable resins, graphene,        and one or more milling media;    -   b. agitating the mixture to disperse the graphene;    -   c. combining the mixture formed in b) with one or more further        curable resins and one or more further milling media, and        agitating to further disperse the graphene; and    -   d. adding milled fibreglass.

Embodiment 69: A method according the embodiment 68, further comprisingadding one or more thixotropic agents, air release, wetting agentsand/or silanes.

Embodiment 70: A method according to embodiment 67 or embodiment 68,further comprising the step of degassing the resin composition.

Embodiment 71: A method of preparing a composite material according toany one of embodiments 28 to 51 comprising curing a resin compositionaccording to any one of embodiments 1 to 27.

Embodiment 72: A method of manufacturing a fibreglass reinforced resinaccording to any one of embodiments 52 to 59 comprising the steps ofspraying a mixture comprising a resin composition according to any oneof embodiments 1 to 27 and fibreglass rovings and curing the resincomposition.

It is understood that the detailed examples and embodiments describedherein are given by way of example for illustrative purposes only, andare in no way considered to be limiting to the disclosure. Variousmodifications or changes in light thereof will be suggested to personsskilled in the art and are included within the spirit and purview ofthis application and are considered within the scope of the appendedclaims. For example, the relative quantities of the ingredients may bevaried or optional ingredients deleted to optimize the desired effects,additional ingredients may be added, and/or similar ingredients may besubstituted for one or more of the ingredients described. Additionaladvantageous features and functionalities associated with the processesof the present disclosure will be apparent from the appended claims.Moreover, those skilled in the art will recognize, or be able toascertain using no more than routine experimentation, many equivalentsto the specific embodiments of the disclosure described herein. Suchequivalents are intended to be encompassed by the following claims.

The invention claimed is:
 1. A resin composition, said resin compositioncomprising: a) one or more curable or cured resins; b) graphene; c) oneor more inert milling media, wherein the milling media is capable ofdispersing graphene; and d) milled fibreglass.
 2. A resin compositionaccording to claim 1, wherein the one or more milling media arehydrophobic.
 3. A resin composition according to claim 1, wherein theone or more milling media are insoluble in the resin composition.
 4. Aresin composition according to claim 1, wherein the crushing strength ofthe one or more milling media is greater than about 2000 psi (13.79MPa), or greater than about 3000 psi (20.70 MPa), or greater than about4000 psi (27.58 MPa).
 5. A resin composition according to claim 1,wherein the one or more milling media have a Mohs hardness of greaterthan about 4, or greater than about 5, or greater than about
 6. 6. Aresin composition according to claim 1, wherein the one or more millingmedia comprise one or more of hollow glass microspheres, cenospheres andexpanded glass aggregate.
 7. A resin composition according to claim 1,wherein the one or more curable or cured resins comprise one or more ofbisphenol A vinyl ester resin, terephthalate resin, terephthalate-NPGresin, isophthalate resin, isophthalate-NPG resin, orthophthalate resin,orthophthalate-NPG resin and urethane acrylate modified resin.
 8. Aresin composition according to claim 1, comprising: a) from about 50 wt.% to about 80 wt. % of one or more curable or cured resins, wherein theone or more curable or cured resins comprise one or more curable orcured polyester resins, vinyl ester resins and epoxy resins; b) fromabout 0.1 wt. % to about 2.0 wt. % graphene; c) from about 0.75 wt. % toabout 35 wt. % of one or more milling media; and d) from about 3.0 wt. %to about 20 wt. % of milled fibreglass; based on the total weight of thecomposite material.
 9. A resin composition according to claim 1, whereinthe graphene has an average platelet size between about 1 micron andabout 100 micron, or between about 5 micron and about micron, or betweenabout 10 micron and about 30 micron.
 10. A resin composition accordingto claim 1, wherein the resin composition comprises hollow glassmicrospheres having a diameter between about 30 micron and about 150micron, cenospheres having a diameter between about 20 micron and about150 micron or both hollow glass microspheres having a diameter betweenabout 30 micron and about 150 micron, and cenospheres having a diameterbetween about 20 micron and about 150 micron.
 11. A resin compositionaccording to claim 1, further comprising one or more accelerators,promoters, inhibitors, air release agents, wetting agents silanes andlow styrene emission additives.
 12. A composite material, said compositematerial comprising a cured resin composition according to claim
 1. 13.A fibreglass reinforced resin comprising the composite materialaccording to claim 12 and further fibreglass.
 14. A fibreglassreinforced resin according to claim 13, wherein the fibreglassreinforced resin has a flexural strength greater than about 124 MPa, orgreater than about 130 MPa, or greater than about 140 MPa, or greaterthan about 150 MPa, or greater than about 160 MPa.
 15. A fibreglassreinforced resin according to claim 13, wherein the fibreglassreinforced resin has a tensile strength greater than about 100 MPa, orgreater than about 110 MPa, or greater than about 120 MPa, or greaterthan about 130 MPa, or greater than about 140 MPa.
 16. A laminatecomprising one or more layers of fibreglass reinforced resin accordingto claim
 13. 17. A swimming pool or spa pool comprising a laminateaccording to claim 16.